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Date of Award

Winter 2023

Document Type

Masters Thesis

Department or Program Affiliation

Energy Science

Degree Name

Master of Science (MS)


Environmental Sciences

First Advisor

Sheikh, Imran

Second Advisor

Sifuentes, Froylan

Third Advisor

Barnhart, Charles


It is widely believed that to reduce CO2 emissions the best strategy is to electrify everything, decarbonize the grid, and improve energy efficiency. This research looks specifically at the use of air source heat pumps (AHP) as a tool to reduce the CO2 emissions of heating energy in the residential sector. The landscape of residential energy use is complicated by a broad range of factors. We compare AHP, natural gas (NG), and electric resistance (ER) heating using data from energy prices, temperature, appliance efficiency, building efficiency and marginal emissions data from 2019 as well as modeled data of what emissions the future grid might produce. With this data we answer the question of what effect AHP units can have on mitigating carbon emissions associated with heating in the residential sector. Using modeled emissions data results show that 37.7% of homes that are currently using NG or ER heating could reduce their emissions by installing a heat pump while realizing an economic saving, another 61.8% could reduce emissions with an added cost. In total 99.7% of BTU’s used for heating in the United States could be delivered with lower emissions using air source heat pumps in place of electric resistance and natural gas. Houses that used other forms of heating or no heating at all were not included in this study. Using data from 2019, in total, 129 million metric tons (Mt) could be mitigated with a net savings of $10 billion at an average savings of $72.74 per tonne. Results show that the mitigation potential for replacing NG heating with AHP is greatly expanded as the grid becomes less carbon-intensive over time while the cost to do so is greatly reduced.




heat pumps, marginal abatement cost curve, emissions reduction, climate change, electrification


Western Washington University

OCLC Number


Subject – LCSH

Air source heat pump systems--United States; Carbon dioxide mitigation--United States; Natural gas--Environmental aspects--United States; Resistance heating--Environmental aspects--United States

Geographic Coverage

United States




masters theses




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